Dust cap



May 17,1927.

E. F. TOBQLD DUST CAP Filed Auz.11. 1920 .4 5. L EEE www; 4 ,/lH i ,f o Egg NWN .A

Patented May 17, 1927.

UNITED STATES PATENT OFFICE.

EWALD F. TOBOLD, 0F CLEVELAND, OHIO, .ASSIGNOR TO THE DIL'L MANUFACTURING COMPANY, A CORPORATION OF OHIO.

DUST CAP.

Application led August 11, 1920. Serial No. 402,845.

The present invention relates to a cap which is so constructed that it inay be quickly attached and detached from a stem such it'or instance as a valve stem.

(-)ne ot the objects of the invention is to provide a dust cap which linstead ot requiringthat the dust cap be threaded over the entire threaded portion of the valve stem, ma be `attached by a few turns ofthe cap an1 requiring only a limited thread engagement between the valve stem and the threaded portion of the cap.

Another object of the invention is to provide a cap which may be attached to the usual valve stems which are at present in use without requirin any special rim nut or other auxiliary attac ment.

Another object` ot the invention is to provide a cap which may be made ot round cross-section with an internal member adapted to secure attachment to the valve stem and as a further object the provision of a construction whereby when the internal member is secured upon the valve stem, the

cap roper vwill be locked to the internal. mem er, and thus `to the valve stem.

Reference should be had to the accompanying drawings `forming a part ot this specification, in which Fig.` 1 is an elevation with portions .in section of a cap embodying my inventionnattached to a valve stem; Fig. 2 is an elevation with portions in section ofthe cap; Fig. 3 is a plan view ol the attaching elements; Fig. 4; is a plan view ot a modified form of the attaching elements.

Referring to the drawings, l indicates a threaded valve stem of well known construction; 2 represents theusual rim nut which is employed in connection with such valve stems; 3 represents the threaded projection of lesser diameter than the main portion o'l' the valve stem which is also the usual construction at present employed.

drawing,the opening is oi. a diameter to receive the threaded extension 3 ot the valve stein. This but indicative ot any torni oi? attachment, and the member 5 may be otherwise attached to the valve stem, and to other portions ot the valve lstem than that shown in the drawing without departingI ifi-om the spirit of this invention.

Where the attaching member is constructed so as to eo-operate with the threaded extension 3 oi the valve stem, the recess (5 at its inner end is provided with a packing Washer 7 which serves as a packing tor the end ot the valve stem. The member 5 also may be provided with an additional depression such as .indicated at 8 which will permit the stem ot the valve inside, such as indicated at 9, to project beyond the threaded portion 3 ot the valve stem.

The attaching member 5 is preterabl'v made ot such a diameter as to snugly tit within the cap portion -l and at its upper end is provided with a shoulder l0 and a portion lll which projects abovev the shoulder l0.

Surrounding the extending portion il and co-operating with the shoulder' l0 is a member which may be termed an expanding member. This member may be generally described a ring like body made ot' material having required springiness or resiliency, the ring member being preferably split so that normally .it springs outwardly into engagement of the inner wall of the cap Il.

' The extension ll and the ring member which siilrrounds the same are so if'ormed that when the attaching member 5 has become attached to the valve stem in placing the cap on a valve stem, the continued rotation of the cap e will cause relative movement between the extension 1l and the ring which co-operates therewith, whereby the split ring member will be further expanded and lock the cap member l against further rotation.

There are various forms which the extension ll and the ring member co-operating therewith may assume. One ot these forms is shown in Fig. 3 wherein the extension ll. is slightly elliptical or eccentric with respect to the central axis ot the member The particular ring member which co-operates therewith is indicated at l2 and is split as indicated at 13. This ring member is of titi SEU

course ot such a diameteras tits within the cap member 4t.

As will be readilyv seen, remembering that the ring;` l2 is in itrietional engagement with the cap-i 4f, when the rap with its i'i'ien'iber :i is introduced onto ay valve stem, and rotation imparted to the cap, the member 5 threads on to the extension 3 ot the valve stem and as soon as this is accomplished the member 5 becomes tixed and continued rotation ot the ap it causes the ring; l2 to turn relative to the projection ll and because ot the eccentric character ot the projection 1t the ring 12 is further expanded and ultimately binds the cap et against further rotation.

Preferably the attachingA member 5 is a tit but slidable within the cap 4t, thus the member 5 majT be positioned to accommodate the cap to cover that part ot' the vvalve stem which in the particular instance majT extend beyond the rim nut or beyond the telloe ot the wheel it a rim nut not used.

It the attaching member 5 occupies a position toward the open end ot' the cap when the attaching operation is commenced, after the member 5 is threaded on to theV valve stem, the cap t may be pushed over the valve stem until the edge of the cap at the open end contacts with the rim nut or with the elloe of the wheel, the tin-ning operation npon the cap continued until the cap is locked. The trictional engagement between the inner end of the cap and the rim nnt or the felloe of the wheel,` it no rim nutbe nsed, assists in holding the cap in its locked posit-ion.

A modified construction which will accomplish the same results as before described is shown in Fig. it. In this construction the extension of the member 5 is indicated at ll and this extension is provided with a plurality of short extensions such as indicated at 11b and between the extensions there are depressions llc.

The co-operating ring member is indicated at 1Q" and it likewise is provided lwith inwardly extending projections lill and intermei'liate depressions 1&2". 'lhe rinej member l2 i; split as indicated at lil, l

The rin;l member l2 is made oll suitable resilient material and when placed in the cap 4l; normall \V sllirings outward into engage-- ment with the inner wall ot the cap. lVhen the member 5 becomes attached to the valve stem, incident to applyinga the dnst; cap. it produces relative rotation between the member l2 and the projection tl which causes the engaging' projections on these two members to ride up on eaeh other and etl'eet a eannning' action between the projection il* and the ringv 12, which expands the ring' t2 into close ltrictional engagementwith the lap L d Various modifications embodying the principle ot operation o'i the herein describtnll cap ma)7 be employed without departing 'trom the spirit ot: this invention.

llaviner described my invention, l. claim:

l. A cap comprising` a shell portion, a member within the shell portion and having means by which it may be attached to a stem, an expansible element associated with said member, said expansible element and the said member cooperatingto canse expansion of the expansible member when the two are relativel)v turned.

2. A cap comprising' a shell portion, an attachingr member therein and haringl means bj' which it may be attached to a stem, said attachingv member having;` a projecting porA tion, an expansible element within the shell and cti-operating with the projeetiimy portion ot the attaching;` n'iember wherelnv the ex pansible element is caused to expand upon relative turning;` movement between the expansible element and the j nfojection on the, attaching`- member.

In testimonjv whereof, I hereunto atiix my signature.

FVALD F. TOBOLD.

till 

